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Over the past few decades, inflation models have been studied by researchers from different perspectives and conditions in order to introduce a model for the expanding universe. In this paper, we introduce a modified f ( R ) gravitational model as ( R + γ R p ) in order to examine a new condition for inflation models. Given that our studies are rel...
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Zusammenfassung
Geldentwertung ist ein weitgehend unerwünschter makroökonomischer Zustand. Um ihn effektiv zu verhindern hilft es, die Entstehung von Inflation zu untersuchen. Die Analyse setzt an den fundamentalen Eigenschaften moderner Volkswirtschaften an.
Citations
... • In the context of modified gravity theories, see e.g. [41][42][43][44][45][46]. ...
Our current best guess for a unified theory of gravitation and quantum field theory (string theory) generically predicts a set of requirements for a consistently quantized theory, the Swampland criteria. Refined versions of these criteria have recently been shown to be in mild tension with cosmological observations. We summarize the status of the current impact of and constraints on the Swampland conjectures from cosmology, and subject a variety of dark energy quintessence models to recently released cosmological datasets. We find that instead of tightening the tension, the new data allows for slightly more freedom in the Swampland criteria. We further demonstrate that if there is no theoretical argument made to prevent interactions of the moduli fields with the electromagnetic sector, a novel fine-tuning argument arises from the extremely tight current constraints on such interactions. Finally, we conclude with a cautionary tale on model-independent reconstructions of the Swampland criteria from expansion rate data.
... So, in this case, gravity is considered as weakest force [5,6]. Of course, there are other conjectures in the swampland program and it helps to find effective fields theories compatible with quantum gravity, for further study refer to [1,2,[6][7][8][9][10]. On the other hand, the weak cosmic censoring conjecture is very important for theoretical physics. ...
... As we have seen, relations (15), (16) and (17) are extremality states of black hole in presence of quintessence and cloud of strings. On the other hand, we showed that relations (8), (9) and (10) are extremality states of black hole in presence of only quintessence. We find here that in the first case there is more freedom parameter b to establish compatibility between WGC and WCCC ( Table 2). ...
One of the important problems with the existence of weak gravity conjecture ( WGC ) is the violation of the cosmic censorship. Such a cosmic phenomena is important and consistent in general relativity. It means that for a charged black hole in four dimensions and in the normal state, the WGC cannot hold due to the violation of the weak cosmic censorship conjecture ( WCCC ). But in this paper, in order to eliminate such a violation, we try to consider RN black hole at two cases, with quintessence, quintessence and cloud of strings in asymptotically flat and non-asymptotically flat. By using such metric background and applying restrictions on its parameters, we show that there will be a good compatibility between WGC and WCCC . Here, we can also see that quintessence case has less freedom in establishing compatibility than quintessence and cloud of strings. Because in the second case, the number of parameters is more and there is a degree of freedom to better establish the compatibility of two theories. Also, here we explain charged black hole in presence of quintessence and cloud of string for Q > M and use some interesting figures we show the corresponding the black hole has an event horizon.
... And third reason for our use of this formulism is that in future it can be a good way to find some universal relation between WGC and AdS/CFT. On the other hand, the weak gravity conjecture (WGC) defines the boundary between swampland and landscape, effective field theories consistent with quantum gravity are placed in the landscape, and inconsistent ones are placed in the swampland [20][21][22][23][24][25][26][27][28][29]. This conjecture considers gravity the weakest force; hence, the Q/M > 1/M p condition is valid (M p is Planck mass) [24,30]. ...
... Second case ω q = −1 By placing equations (27), (28), (8) and (5) in equation (2) in which case, equation (2) is rewritten as below, ...
... Therefore, when b = 1 or C = 1, the black hole will have an event horizon. But the first condition is not acceptable because by using relation (27), S c and r c become zero and this is physically meaningless. In this case, the only condition C = 1 remains to preserve WCCC. ...
In this paper, we first introduce the Riesner-Nordstrom AdS (RN-AdS) black hole in presence of quintessence and cloud of strings. And then we use the Restrict Phase Space (RPS) formalism in the corresponding black holes at the critical point with equation state . We take advantage from the central charge and Newton's constant with form of variable and prove the compatibility between weak gravity conjecture (WGC) and weak cosmic censorship conjecture (WCCC). Here, we show that when we use the usual RN-AdS black hole with condition, we have weak gravity conjecture. But, in that case, the WCCC is violated by WGC conjecture. In order to avoid such violation, we consider the Riesner-Nordstrom AdS (RN-AdS) black hole in the presence of quintessence, quintessence, and cloud strings. Here, also one can say that, by using the special central charge, chemical potential, appropriate quintessence, cloud strings parameters, and the effective Newton's constant with suitable conditions one can arrive the compatibility between weak gravity conjecture and weak cosmic censorship conjecture.
... Therefore, the swampland program was introduced. This program includes many conjectures, including weak gravity conjecture (WGC), dS and AdS conjectures, SWGC, SSWGC, TCC, etc. [1][2][3][5][6][7][8][9][10][11][12][13][14][15]. The collection of effective low-energy theories compatible with quantum gravity lives in the landscape. ...
In this article, we want to check four inflation models, namely, composite NJL inflation (NJLI), Glueball inflation (GI), super Yang–Mills inflation (SYMI), and Orientifold inflation (OI), with two conjectures of the swampland program: scalar weak gravity conjecture (SWGC) and strong scalar weak gravity conjecture (SSWGC) since all these models violate the dS swampland conjecture (DSC) but are compatible with further refining de Sitter swampland conjecture (FRDSSC) through manual adjustment of free parameters of the mentioned conjecture. We want to study the simultaneous compatibility of each model with these two new conjectures. Despite being consistent with (FRDSSC), we find that all models are not compatible with the other conjectures of the Swampland program in all regions, and these conjectures are only satisfied in a specific area. Moreover, due to the presence of constant parameter (ϕ0) in the higher orders derivatives, the (SYMI) and (OI) among all the models are more compatible with all conjectures of the swampland program. These models can provide a more significant amount of satisfaction with all of them. They can be suitable and accurate inflation models for a more profound examination of universe developments. We determined a particular region for these models is compatible with (FRDSSC), (SWGC), and (SSWGC) simultaneously.
... A typical method of breaking higher form global symmetries includes charged conditions. While exclusively if the charged conditions spectrum exists entire, can one break the whole group [36][37][38][39][40][41][42][43][44][61][62][63][64][65][66][67][68][69]. ...
We search for a possible relation between weak gravity conjecture and conformal field theory in the hyperscaling violating and Kerr-Newman-AdS black holes. We deal with the critical points of the black hole systems through the correlation function introduced in conformal field theory. We discuss the weak gravity conjecture conditions by the imaginary part of the energy obtained from the critical points and their poles. Under the assumptions z=1, d=1 and , we link weak gravity conjecture to the hyperscaling violating black holes due to the existence of larger and smaller than one. As the second black hole system, we study the conditions of weak gravity conjecture for the Kerr-Newman-AdS black hole by rotation and radius parameters. Then, we show that the conditions of weak gravity conjecture are satisfied when the charged particle near the hyperscaling violating and Kerr-Newman black holes is with a ratio . Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
... Although the swampland program is a nascent idea and still has problems, it is being modified, adding new conjectures. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Recently, researchers benefited from refined dS swampland conjecture in studying many inflation models due to different conditions such as slow-roll and constant-roll conditions with respect to other frameworks. [17][18][19][20][21][22] Many inflation models contradict these conjectures and cause problems, which have led to introducing new conjectures or correcting the intended conjecture. ...
... In the above equation, each of the parameters M p , h ij , and R 4 specifies the Planck mass, the field metric, and 4d Riemann curvature. The refined dS swampland conjecture expresses that if the effective theory of quantum gravity satisfies the following conditions, they can be considered in the landscape instead of swampland [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17], ...
... Of course, there are models in the literature that are fully compatible with the refined swampland conjecture [36,37]. Therefore, we check the mentioned models in this paper that are inconsistent with the previous conjecture with further refined dS swampland conjecture in the equation (5) and describe the results thoroughly. We will also compare the results with each other. ...
In this paper, we challenge some inflationary models with the recent new conjecture of the swampland program, namely, further refining the de Sitter swampland conjecture. So far, different inflation models have been studied with refined dS swampland conjecture in various conditions. Some of these models were in line with this conjecture, and some were in direct tension with it. Therefore, a modified model that combines the first and second conditions of refined dS conjecture was proposed. It has a limitation on its constant parameters such as a, b=1−a and q. We challenge several inflation models with the new conjecture, which contradicts the refined dS conjecture. We discuss the constraints and adjustments of each of a, b=1−a, and q and the compatibility or incompatibility of the inflation models with further refining the de Sitter swampland conjecture. We will compare the results with the models studied by refined dS conjecture. We conclude that many inflation models are fully compatible with the mentioned conjecture. If the new conjecture is accurate, these inflationary models live in the landscape instead of the swampland.
In this paper, using Hamiltonian formalism, we obtain solutions for constant-roll inflation according to the non-commutativity and the non-minimal coupling field of Lagrangian. We consider three different types of couplings: power-law, exponential, and logarithmic. Then, by plotting some figures, we study the effects of these coupling in constant-roll inflation with non-commutative parameters. We identify and specify the permissible regions of each case about swampland conjecture and determine the best model. We find that the exponential coupling, logarithmic coupling, and power-law coupling with agree with the dS swampland conjecture. These couplings give us similar results in both cases, some of which are compatible and some incompatible with the dS swampland conjectures. Moreover, is more compatible than and the consistency value in the second boundary condition is much higher than in the first. The order of better compatibility of couplings with the Swampland Conjecture is ranked as follows: exponential non-minimal coupling, logarithmic non-minimal coupling, and power-law non-minimal coupling. For each type of coupling, we calculate the values of the scalar spectral index and the tensor-to-scalar ratio r for two different potentials and compare them with the observational data from Planck 2018. We also determine the range of the free parameters (a,b,q) of the further refining de Sitter swampland conjecture (FRDSSC) that make the model consistent with the conjecture. We find that the model satisfies the FRDSSC for all types of couplings and both potentials, with some constraints on the parameters.
In this paper, we conduct a comprehensive investigation into the weak cosmic censorship conjecture (WCCC) for Reissner-Nordstr\"om (R-N) AdS black holes that are influenced by Perfect Fluid Dark Matter (PFDM). Our study is framed within the context of Conformal Field Theory (CFT) thermodynamics. We delve into the principles of energy flux and mass-energy equivalence to explore the interplay between the weak gravity conjecture (WGC) and the WCCC. Our analysis begins by examining the interaction between incoming and outgoing energy fluxes, which induces changes in the black hole's properties. By applying the first law of thermodynamics, we assess the validity of the second law in these dynamic scenarios. We also consider equilibrium conditions that involve both absorption and superradiance processes. Utilizing the framework of black hole thermodynamics within CFT, we demonstrate that the WCCC is upheld if the black hole is in or near an extremal state, particularly when it is subjected to radiation and particle absorption. This finding is significant as it reinforces the robustness of the WCCC under these specific conditions. Furthermore, we uncover additional insights by employing mass-energy equivalence principles and conducting second-order approximations near the extremality state. Specifically, we find that when a black hole radiates and its central charge surpasses the scaled electric charge, the emitted superradiant particles adhere to the WGC. This adherence results in the black hole moving away from its extremal state, thereby maintaining the WCCC.
In this study, we investigate the Weak Gravity Conjecture (WGC) and Weak Cosmic Censorship Conjecture (WCCC) for a quantum-corrected Reissner-Nordstr\"om Anti-de Sitter (RN-AdS) black hole embedded in Kiselev spacetime. By making small perturbations to the action and using WGC, we investigate the stability of black holes and predict the existence of lighter particles in the spectrum. Using the scattering of a charged scalar field, we study the WCCC. We verify under certain conditions on the temperature of the black hole, the second law holds for near-extremal black holes. Finally, we demonstrate that the WCCC holds for both extremal and near-extremal black holes.